From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753280AbeDUVeW (ORCPT ); Sat, 21 Apr 2018 17:34:22 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:36486 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753150AbeDUVeV (ORCPT ); Sat, 21 Apr 2018 17:34:21 -0400 Date: Sat, 21 Apr 2018 14:34:01 -0700 From: Matthew Wilcox To: Souptick Joarder Cc: viro@zeniv.linux.org.uk, mawilcox@microsoft.com, ross.zwisler@linux.intel.com, akpm@linux-foundation.org, dan.j.williams@intel.com, mhocko@suse.com, jack@suse.cz, kirill.shutemov@linux.intel.com, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3] fs: dax: Adding new return type vm_fault_t Message-ID: <20180421213401.GF14610@bombadil.infradead.org> References: <20180421210529.GA27238@jordon-HP-15-Notebook-PC> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180421210529.GA27238@jordon-HP-15-Notebook-PC> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Apr 22, 2018 at 02:35:29AM +0530, Souptick Joarder wrote: > Use new return type vm_fault_t for fault handler. For > now, this is just documenting that the function returns > a VM_FAULT value rather than an errno. Once all instances > are converted, vm_fault_t will become a distinct type. > > commit 1c8f422059ae ("mm: change return type to vm_fault_t") > > There was an existing bug inside dax_load_hole() > if vm_insert_mixed had failed to allocate a page table, > we'd return VM_FAULT_NOPAGE instead of VM_FAULT_OOM. > With new vmf_insert_mixed() this issue is addressed. > > vm_insert_mixed_mkwrite has inefficiency when it returns > an error value, driver has to convert it to vm_fault_t > type. With new vmf_insert_mixed_mkwrite() this limitation > will be addressed. > > As new function vmf_insert_mixed_mkwrite() only called > from fs/dax.c, so keeping both the changes in a single > patch. > > Signed-off-by: Souptick Joarder Reviewed-by: Matthew Wilcox There's a couple of minor things which could be tidied up, but not worth doing them as a revision to this patch.